3.0 V6 BiTDi rattling noise around 1500rpm

[I2ich83]

Hi I've recently purchased a 2013 A6 BiTDi with 122k miles, it does have full service history how[]ever some of the intervals were around 15-20k! By Audi and more recently 10k intervals.

The problem is between 1200-1500rpm there is a rattling noise which seems to be coming from the back of the engine and the car starts to vibrate as it's rattling, the noise is quite noticeable especially when cold! Does this sound like loose timing chain rattling?
I have checked the camshaft adaptation using odb live data and it's around -2.60 when cold. So according to this it is slightly stretched but not upto the -5.00 or +5.00 so maybe the problem is something else?

Any advice welcome thanks.

https://photos.app.goo.gl/vX1XP563AKCrbnnv9

[johnsimcox]

Can't comment on the sound but there are many on here with the skills and knowledge to do that. Sounds like the PO had the car serviced on the variable servicing regime which dictates a service at least once every 2 years/20k miles but is triggered by the car monitoring usage and oil quality. More recently the car appears to have been serviced on the fixed schedule of annually or every 10k miles.

[Crasher]

The long life intervals wears the chain system which is why it went back to fixed intervals but it was too late; they are a MASSIVE job to replace, takes a very seasoned pro around four days and a huge pile of parts.

[I2ich83]

Yep I'm aware of the long life service BS that has lead to a lot of engine problems! I've already had a few quotes for the timing chain I know it's a very big job!

Could it possibly be the water pump bearing as there is also a little dried up coolant around the water pump. I can't see any leaks in the V but it's hard to see right in there. It's going in to have the water pump replaced as a hope that it's this and not the timing chain rattling. Before I go for the big job!!

[I2ich83]

The long life intervals wears the chain system which is why it went back to fixed intervals but it was too late; they are a MASSIVE job to replace, takes a very seasoned pro around four days and a huge pile of parts.

Here is another video clip from today when the car was cold you can hear it gets a lot louder around 1700rpm it's pretty silent on start up no ratte at all.

Engine noise BiTDi

[Crasher]

Difficult but it does sound chain like.

[bluezie]

My guess is the dual mass flywheel is breaking up, especially if the engine is vibrating. Can you feel the vibrations through the floor? Worn cam chains on their own shouldn't produce vibration, unless they were so bad that erratic timing and mis-fires are happening, but you'd get a 'no correlation' cam / crank fault code, and mis-fire fault codes etc.
I feel for you, as I fear at best it's box out and hope it's just the DMF, or engine out for a BIG strip down.
I'm glad mine has been on 10K oil changes since 30K (18K was the first service so it really shouldn't be a problem) It's on 95K and no cam chain noise so far.....

[jbmercapple]

Didn’t think the Bitdi had a DMF?

[bluezie]

Didn’t think the Bitdi had a DMF?

Normally the 8sp ZF auto has the DMF as part of the torque converter, or 'Twin Torsional Damper' as they call it. But does the same job as any other DMF, no idea on reliability, or whether they were fitted to all applications of the ZF box?